1. Field of the Invention
The present invention relates to a data entry control device which causes an operation unit to perform efficient operations in the case where the data transfer rate of a continuous signal is identical to or lower than the speed with which the operation unit performs operations on the continuous signal and a control method therefor.
2. Description of the Related Art
In the field of recent signal processing systems, there is a requirement for a mode of signal processing in which a signal measuring instrument is carried aboard an aircraft, an operation processing unit is located on the ground, and a signal measured in the aircraft and transmitted to the ground and a signal measured by a ground signal measuring instrument are correlated in the ground operation unit using an operation such as fast Fourier transform (FFT).
In this mode, a continuous signal (analog signal) to be operated on is measured, then converted to a digital signal by an analog-to-digital converter in each of the signal measuring instruments. The resulting digital signals are then entered into the operation unit where an operation, such as FFT, is performed on the input signals.
If the signal measuring instruments for measuring signals to be operated on are changed, the transfer rate of data from the instruments to the operation unit may vary, depending on the type of signal measuring instrument. In such a case, it will be required to change the timing of operations in the operation unit.
In most cases, the signal measuring instrument aboard an aircraft is quite a distance from the signal measuring instrument located on the ground. Thus, considerable delay will be involved in transferring data to the ground, and the amount of delay will also vary widely because the speed of the aircraft is very high. For this reason, it is required to change the timing of operations in the operation unit in accordance with the amount of delay.
In a conventional signal processing system, the operation rate of the operation unit is synchronized with the transfer rate and the amount of delay of input data. This reduces the operation efficiency of the operation unit. As a result, the efficiency in use of the operation unit by other processing than the operation processing will also be decreased, thus reducing the processing performance of the whole system.